Pentacyclic and tetracyclic terpenoids form a part of a group of naturally occurring substances (isoprenoids) that show a large range of biological activities (Dzubak, P.; Hajduch, M.; Vydra, D.; Hustova, A.; Kvasnica, M.; Biedermann, D.; Markova, L.; Urban, M.; Sarek, J. Nat. Prod. Rep. 2006, 23, 394). Among the substances showing an excellent in vitro cytotoxic activity belongs, e.g., betulinic acid. The cytotoxic activity of some triterpenoid derivatives is mentioned in patent literature (Hajduch M., Sarek J.: Triterpenoid derivates. PCT Int. Patent Appl. WO0190136, 23 May 2001; Hajduch M., Sarek J.: Triterpenoid derivates. PCT Int. Patent Appl. WO0190046, 23 May 2001; Hajduch M., Sarek J.: Triterpenoid derivates. PCT Int. Patent Appl. WO0190096, 23 May 2001).
So far, only few terpenic 2-deoxy glycosides were synthesized. First, they were prepared by reaction with NIS (N-bromosuccinimide), wherein the formed 2-deoxy-2-iodo glycosides yielded acetylated 2-deoxy glycosides by reaction with 10% Pd/C or reacted with methanolic KOH solution, yielding free 2-deoxy glycosides (Flekheter, O. B.; Baltina, L. A.; Vasileva, E. V.; Tolstikov, G. A.: Russ. Chem. Bull. 1996, 45, 2993).
Later, triterpenic 2-deoxy glycosides were prepared using katex in H+ cycle and lithium bromide in a mixture of acetonitrile and dichloromethane (Flekheter, O. B.; Baltina, L. A.; Tolstikov, G. A.: J. Nat. Prod. 2000, 63, 992). The reaction is quenched by triethylamine and followed by deacetylation by methanolic KOH. When glycals are used, α-anomers of 2-deoxy glycosides are formed.
Several 2-deoxy glycosides of naturally occurring and synthetic oleanane, lupane and ursane hydroxy derivatives were already prepared by these two methods; among oleanane derivatives were, e.g., 2-deoxy glycosides of glycyrrhetic acid derivatives (Flekheter, O. B.; Baltina, L. A.; Vasileva, E. V.; Tolstikov, G. A.: Russ. Chem. Bull. 1996, 45, 2993), allobetuline 2-deoxy glucoside (Baltina, L. A.; Flekheter, O. B.; Vasiljieva, E. V.: Mendeleev Commun. 1996, 6, 63), among lupane derivatives betulin-28-acetate-2-deoxy-L-arabinoside may be listed (Flekheter, O. B.; Baltina, L. A.; Tolstikov, G. A.: J. Nat. Prod. 2000, 63, 992). Also, the preparation of acetylated cholesterol 2-deoxy-glucoside was published (Bollit, V.; Miostovski, C.; Lee, S. G.; Falck, J. R.: J. Org. Chem. 1990, 55, 5812).
The patent application Sarek, J. et al.: WO 2008/037226 teaches the preparation of soluble formulation containing inclusion complexes of cyclodextrins and triterpenoid derivatives, inter alia several 2-deoxy glycosides showing a better bioavailability, but does not describe any activity of such compounds.
The present invention provides novel triterpenoid 2-deoxy glucosides having cytotoxic activity.